import math

def calculate_sector_area(r, angle):
    """
    计算扇形面积
    :param r: 半径
    :param angle: 角度
    :return: 扇形面积
    """
    return math.pi * r ** 2 * angle / 360

area1 = calculate_sector_area(160, 30)
area2 = calculate_sector_area(60, 15)
area3 = calculate_sector_area(30, 16)

print(f"扇形1的面积是{area1:.2f}")
print(f"扇形2的面积是{area2:.2f}")
print(f"扇形3的面积是{area3:.2f}")